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Magnetising Inductance / Primary Inductance

if the magnetising inductance (which the primary inductance) is defined as 100uH then why it is seperated as 100uH and 10mH on the primary ? This is my question. Without the parasitics, a real-world ...
Rohat Kılıç's user avatar
0 votes

Is this PFC choke design correct?

Beware of proximity effect which is the other eddy loss. At lower frequencies like 200 kHz, proximity effect losses will be much higher than skin effect losses. I quickly whipped up some loss ...
qrk's user avatar
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2 votes
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Is this PFC choke design correct?

Your calculations are more or less correct and consistent. The choice or range of options can be improved, however. Don't worry about litz: it's not at all needed for such a low ripple fraction. I ...
Tim Williams's user avatar
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Transformer modelling / coupled inductors

In the beginnig of V2 equation in the picture where does the n.Lm come from ? The inductor's voltage-current relationship is:- $$ v_L = L \ \frac{di_L}{dt} $$ The voltage across the primary ...
Rohat Kılıç's user avatar
5 votes
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Calculation of inductance

\$µ\$ is magnetic permeability(1 in air) Nope. \$\mu\$ is the product of the relative permeability of the core material (air/vacuum, ferrite, whatever), \$\mu_r\$, and the air/vacuum permeability, \$\...
Rohat Kılıç's user avatar
0 votes

Inductor and capacitor in parallel should not yield resultant current in phase w/ voltage

Not totally wrong but deceptive, as a reader might think that the inductive load is an inductor. Maybe it is more clear when in context.
Fred's user avatar
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2 votes
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Inductor and capacitor in parallel should not yield resultant current in phase w/ voltage

"Inductive load" here means a load with an overall inductive component to its current in addition to any in-phase current, not a purely inductive load. I.e. a phase angle between 0 and +90. ...
vir's user avatar
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0 votes

Why does the reciprocal of sum of reciprocals relationship appear commonly?

Take 3 resistors in parallel. There are three paths for current to take. Total current is given by Kirchhoff's Current Law. $$I_T = I_1 + I_2 + I_3$$ Apply Ohm's Law to currents. $$\frac {V_T} {R_T} =...
StainlessSteelRat's user avatar
3 votes
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Skin effect of wires with increasing frequency

For receiver use, don't worry about current handling (as long as it's enough to avoid overheating). Q factor is almost certainly more important. Determine Q from required bandwidth, insertion loss ...
Tim Williams's user avatar
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3 votes

Skin effect of wires with increasing frequency

Skin effect increases the AC resistance of the wire, by decreasing the area available for current to flow. This reduces the Q of inductors. It reduces the sharpness and increases the loss of filters. ...
Neil_UK's user avatar
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0 votes

How to know what size diode to use for inductive spiking?

The diode needs to be able to handle the current that is flowing through the inductor when the transistor is conducting. This is because the current through an inductor can't change abruptly. However ...
feynman's user avatar
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2 votes

How to know what size diode to use for inductive spiking?

You really should look into Transorbs for this, acronym TSB. Although they have a power ratings, they are designed for short duration surge events. Incidentally they are available in both unipolar ...
dougp01's user avatar
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3 votes
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How should we calculate L (inductance) value for a transformer

A starting point would be 20 % magnetizing current of your full rated load, in this case 2 VA. At 230 V, that’s 8.6 mA. Z = 2*Pi*L*f. Solve for L. If the transformer would have been 2 kW, about 5 % ...
winny's user avatar
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0 votes

How should we calculate L (inductance) value for a transformer

The inductance is essentially a characteristic of the transformer core, and rises with the square of the number of turns. If you study the datasheet for a particular core you should find this value ...
Frog's user avatar
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1 vote

Why does the reciprocal of sum of reciprocals relationship appear commonly?

It simply means that the unit you're using for this measurement is the reciprocal of the quantity that you're actually adding. When you put two resistors in series, you're literally adding more ...
hobbs's user avatar
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5 votes
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Why does the reciprocal of sum of reciprocals relationship appear commonly?

Resistance isn't the only descriptor of the behaviour of a resistor. That same behaviour could be represented by the reciprocal of resistance, which is conductance (usually called \$G\$): $$ G = \frac{...
Simon Fitch's user avatar
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1 vote

Why does the reciprocal of sum of reciprocals relationship appear commonly?

It appears in many contexts, as it's the sum of the harmonic mean of the elements, one of the ways of finding the "most normal value" of a set of values. Typically it's used for rates, such ...
jonathanjo's user avatar
8 votes

Flyback Diode Forward Voltage

At the instant of commutation (the voltage reversal), the inductor tries to maintain the exact same current flow. It doesn't try to impose a voltage anywhere, it just forces that current through ...
Simon Fitch's user avatar
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6 votes
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Flyback Diode Forward Voltage

After it turns on, the forward voltage across the diode will be the forward voltage of the diode at the current that was just going through the inductance. This is a characteristic of the diode at ...
Spehro Pefhany's user avatar
3 votes
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How does the leakage inductor distribute over multiple coupled inductors?

With a factor like kc=0.9, energy should be low, and bandwidth should be "low" ... You should use "inductor" something like this. Simulated with "AC Analysis" with ...
Antonio51's user avatar
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15 votes

LCR Meter U1733C "rn" Symbol Meaning

That's an m; the meter currently reads 782.9 mH. By turning off the "r"-shaped segment, it can also be an n, for nanofarads or nanohenries. This type of segment reuse is very common with ...
Hearth's user avatar
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1 vote

Why inductor don't discharge completely even when the duty cycle is 50%?

I'll answer your question with another question: How could the current be discontinuous? Consider an inductor charged to some current, then discharging into an ideal diode and resistor. The current ...
Tim Williams's user avatar
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14 votes
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What is this component - 8 legged inductor?

It's not an inductor. It's a transformer for a DC/DC converter, made by Epcos which is now a part of TDK. Likely a custom order product for this specific product so likely no public data sheet ...
Justme's user avatar
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1 vote

Are inductors in resonant circuits dangerous? They produce very high voltages

It is true that at resonance, voltage across an inductor in a resonant circuit can be large...especially so if resonant components have high Q (quality factor). If one is building a power oscillator, ...
glen_geek's user avatar
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3 votes

Are inductors in resonant circuits dangerous? They produce very high voltages

When you touch it, the human body will be adding capacitance to that circuit model, so it will quickly drop out of resonance. Thus, only the small charge in the cap at the time of touch will discharge ...
Aaron's user avatar
  • 8,061
1 vote

Are inductors in resonant circuits dangerous? They produce very high voltages

They can be, just like any circuit that generates high voltages can be dangerous, regardless of if it uses resonance, charge pumps, electromagnetic conversion, etc. Resonance requires specific ...
vir's user avatar
  • 20.4k
1 vote

What is the function of the inductor in this Bluetooth audio module?

It's meant for filtering the supply power, though I'm not convinced it's a good idea to use an inductor here. If you have a dirty supply, or if you need to keep noise from the bluetooth module out of ...
Hearth's user avatar
  • 35.3k
0 votes

What is the function of the inductor in this Bluetooth audio module?

The inductor is not mandatory for the operation of the module, however it is recommended to prevent noise in audio and stability issues with Bluetooth. It serves the purpose of filtering the power ...
vorobey's user avatar
  • 103
3 votes
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What happens when you insert an inductor between Vcc and a MOSFET's drain?

I think there are a couple of big reasons why you are not able to predict the voltages present in your simulation: Maximum current through the inductor and MOSFET is ambiguous, since \$R_{DS}\$ is ...
Simon Fitch's user avatar
  • 39.2k
3 votes

What happens when you insert an inductor between Vcc and a MOSFET's drain?

Assuming an ideal switch, we can analyze this with a two-phase solution. Assume initial conditions from the previous cycle (periodic steady state). While the switch is on, ...
Tim Williams's user avatar
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3 votes
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Why inductor don't discharge completely even when the duty cycle is 50%?

What you see is a typical steady-state transient response of the LR circuit. As you have noticed at the beginning we first apply 12V across the circuit. And after \$10\mu s\$ the voltage across the ...
G36's user avatar
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2 votes

Why inductor don't discharge completely even when the duty cycle is 50%?

I only see a voltage curve, and that one gets messed up by the potential change when the transistor opens and closes. I'm sure you can set up the simulation tools to plot the current curve flowing ...
Turbo J's user avatar
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0 votes

What happens when you insert an inductor between Vcc and a MOSFET's drain?

You must be more careful when making schematics: - ... Or you will get confusing results. Your 2nd diagram is correct. The inductor will produce a flyback voltage when the MOSFET turns off. So, if ...
Andy aka's user avatar
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2 votes
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Are there safety concerns with hooking an inductor to a MOSFET and generating 85V spikes from a 9V source?

The breadboard will probably be fine, but anything above ~30VDC cannot be considered touch safe. In addition, the circuit you have does not regulate its output so the 85V figure could be low or high ...
vir's user avatar
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0 votes

Freewheeling diode in a capacitor

I'd say the 'symmetry' logic is not fully applied here. The diode at inductor is added to take care of the situation when the current through the inductor (tries to) decay, the inductor (tries to) ...
quetzalcoatl's user avatar
1 vote

Connecting the LC circuit to dc voltage source without transient

I have been looking for a control algorithm how to achieve a state when both of the upper transistors are open and this state has been achieved without transient in the LC circuit. I don't believe ...
Andy aka's user avatar
  • 465k
0 votes

Freewheeling diode in a capacitor

The large current surge can certainly be a problem for the capacitor, but to avoid it a parallel diode, like the freewheeling diode, would not help (and a diode in series would block all current!) So ...
Jos Bergervoet's user avatar

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